About VictorBG

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Hello!
I am a fresh beginner in the domain of embedded systems and this MSP430F5529 is my very first development board. I am now trying to make an ADC conversion and send it through the UART to try a signal treatment algorithm with real-world values.
I used an example code in Energia that i modified a little bit:
void setup() {
// initialize serial communication at 9600 bits per second:
Serial.begin(9600);
// Comment: I see many people preferring the 115200 BR for this board.
// Is there a particular reason for this choice?
}
// the loop routine runs over and over again forever:
void loop() {
// read the input on analog pin A3:
int sensorValue = analogRead(A3);
// Comment: I think the F5529 actually writes its ADC results on 12 bits.
// Should i try to use a long, 16-bit integer?
// print out the value you read:
Serial.println(sensorValue);
}
The Energia console gives me expected readings, using an AA battery and an old function generator. For my first UART tests, I tried using Processing, a multipurpose javascript program that i use for drawing.
import processing.serial.*;
float[] y; // Array to contain the values read through the UART
Serial myPort; // Create object from Serial class
int val; // Data received from the serial port
void setup()
{
// I define the size of the drawing board to be 600 X 400 pixels.
size(600, 400);
// I initialize my 'y' array
y = new float[width];
for(int i = 0; i<width; i++){
y[i] = 0.0;
}
// This is to open the correct port. The number in square brackets might vary.
String portName = Serial.list()[3];
// Here i define the baudrate, so it's the same as the one in Energia.
myPort = new Serial(this, portName, 9600);
}
void draw()
{
// This draws a white background
background(255);
// This tells that i want to draw with the color black.
stroke(0);
for (int i = 0; i<width; i++){
// For every entry in my 'y' array, I draw a black dot.
point(i,y[i]);
}
// I read a new value from the UART and feed it to my "update" routine.
val = myPort.read();
update(val);
}
void update(int value){
// I shift every value to the left in my array.
// This is to get a "strip-chart" feeling to my graph.
for (int i = 0; i<width-1; i++){
y[i] = y[i+1];
}
// For the last value, i use the value read from the serial port.
// I convert it so that i have a correspondance:
// min(UART) = bottom of screen, max(UART) = 2^12 - 1 = 4095 = top of screen.
y[width-1] = (float)height - value * (float)height / 4095.0;
// I also print the UART read value to this software's console for debugging.
print(value,"\n");
}
What prints on the console is a repetitive pattern of something like 13-10-48-13-10-48-etc. when my pin is grounded. When it's not grounded i get pretty much the same exact numbers with a little bit more variations.
At first I thought it was a long int problem with the UART, beacause of the 12-bit ADC conversion, but i'm not so sure anymore.
Help me!
Thank you very much!
readVoltage_ver1.ino